Automatic switch for electric pumps.



No. 707,967. Patented Aug. 26, |902.

A. C. GRISCM. AUTOMATIC SWITCH FOB ELECTRIC PUMPS.

(Application led Nov. 12, 1901.)

(No Model.)

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UNITED STATES PATENT OEETCE.

ALFRED O. GRISCOM, OF NEV YORK, N. Y., ASSIGNOR OF ONE-HALF TO RICHARDCOLLINGS, OF NEW YORK, N. Y.

AUTOMATIC SWITCH FOR ELECTRIC PUMPS.

SPECIFICATION forming part of Letters Patent No. 707,967, dated August26, 1902. Application led November 12, 1901. Serial No. 81,983. (Nomodel.)

T0 a/ZZ whom it may concern,.-

Be it known that I, ALFRED C. GRIsooM, a citizen of the United States,and a resident of the borough of Manhattan, in the city and State of NewYork, have invented a new and useful Automatic Switch for ElectricPumps, of which the following is a specication.

Myinvention relates to an automaticrswitch for electric pumps, with theobject in view of providing simple and veffective means for maintainingthe pressure in the reservoir or vessel supplied by the pump within verynarrow limits of variation.

A practical embodiment of my invention is represented in theaccompanying drawings, in which- Figure l is a view of the switch andits operating mechanism in front elevation, the solenoids being shown insection; and Fig. 2 is a rear view of the same.

o represents a plate, preferably of non-conducting material-such, forexample, as hard rubber. It is here shown as oblong rectangular in form;but its shape may be changed at pleasure,as its purpose is simply toform a support for the several parts to be hereinafter described. Theplate a. may be provided with any well-known or approved means (notshown) for attaching it in the desired position relative to the vesselor reservoir in which the pressure is to be maintained by the pumpcontrolled by the switch. As the pump and reservoir form no part of' mypresent invention, they are not shown and may be of any Well-known andapproved form. For the purposes of my present invention the circuitconnecting the pump is indicated by the word pump,7 and the circuitleading to the main line for supplying electricity to the switch isdenoted by the words mainline. The connection with the reservoir orvessel in which the pressure is to be maintained is made through anipple b on the back of a clip c, fixed to the top of the plate a andprovided with a tubular standard d, which forms a support for apressure-gage e of well-known or approved form, the iiuid being admittedto the interior of the gage through the nipple b and standard d to movethe pointer e of the gage over the dial-plate e2. The central arborfilet the gage,on which the pointer e' is iixed,is

extended through the back of the gage, as shown in Fig. 2, either bymaking the arbor suiiiciently long to project through or by attaching anextension to the said arbor, and a radial arm el is mounted on saidarbor and so close to the back plate of the gage as to produce africtional contact sufficient to hold the arm e4 against displacementduring the rotary movement of the arbor e3. The arm eA1 is provided witha head e5, the side walls of which are spaced from each other to permitthe free end of a vibrating contact-tonguef a limited movement betweenthem. The vibrating contact-tongue f' is fixed on the arbor e3 to rotatetogether with the pointer e' of the gage, and its freeend is in positionto make contact with each of the two contact-pins g g', set in theopposite walls of the head e5. The head e5 is conveniently provided witha small screw e, tapped therein and extending slightly beyond theperiphery of the gage for the purpose of swinging the arm c4 and becauseof the engagement of the tongue fwith either the pin g or g', at thesame time swinging the tongue f and the arbor e3 and pointer e intoposition to set the pointer at the degree of pressure to be maintained.When so set, the arm c4 will remain xed in position until positivelymoved to some other predetermined degree, and the tongue f, togetherwith the arbor and pointer e', will vibrate within the narrow limitbetween the contactpins g g as the pressure falls below and rises to thepredetermined degree to be maintained. The contact of the tonguefwiththe pin g orpin g serves to energize the one or the other of twosolenoids or the one or the other section of a single solenoid to startand stop the action of the electric pump for maintaining the pressure inthe reservoir to which the gage is connected, as follows: The solenoidfor making and breaking the circuit for starting and stopping the actionof the electric pump is conveniently formed in two sections (denoted byIt h) wound on a single spool and separated by a central partition h2.The opposite ends of the spool are provided with supporting-bars-in thepresent instance two barsextending from each of its two opposite ends,those extending from one end being denoted by t t" and those from theopposite end IOO being denoted byjj. These bars are fixed at their outerends to short posts extending oppositely from the face ofthe plate a,those at one end being denoted by 7i: 7c' and those at the opposite endbeing denoted by Z Z'. The barst' i and jj are connected at their endstoward the endof the spoolbyapiece ofinsulatedmaterial m, forming asupport for a central bearing fit for supporting one end of thereciprocating core o. The rods or bars j 7" at the opposite ends of thespool support a piece of insulating material m', which in turn supportsa bearing n', in which the opposite ends of the reciprocating coreslide. At the outer ends of the bars t' t" andjy" are pieces ofinsulating material p p', respectively, which pieces of insulatingmaterial in turn support pairs of spring contact-jaws, those at one endbeing denoted by q q' and those at the opposite end being denoted by ryr. The spring contactjaws q q and r r are adapted to receive betweenthem the outwardly-projecting ends of the core o, the said projectingends of the core being rounded, and the outer edges of the jaws beingturned outwardly for the purpose of causing the ends of the core toenter and force the jaws apart to insure a perfect contact.

In order to overcome the inertia of the reciprocating core 0 and alsothe friction between its opposite sides and the jaws with which it isengaged and at the same time keep the solenoid within moderatedimensions andresistance, I have provided a sliding auxiliary core o',which has a limited movement between the collars o2 o3 on the core. ThisauX- iliary core o being perfectly free to slide on the core o will takethe initiative as the one or the other of the solenoid-sections becomesenergized, and by means of the momentum which it generates during 'itsshort quick movement it will strike the one or the other of theshoulders o2 o3 on the core, giving the core o a quick impulse, as fromthe stroke of a hammer, sufficient to release it from the jaws q q" or rfr', when its further and complete movement will readily take placeunder the influence of the energized solenoidsection.

The wires leading from the main line to binding-posts on the plate a aredenoted by ss', and those leading from the pump to binding-posts on theplate a are denoted by t t. The wire s connects by branch wires u u withthe jaws q and fr, respectively. The wire s connects by branch wires vfn with the vibrating tongue f and with the pump-wire t, respectively.The pump-wire t connects by wires w fw with the contact-jaw r and withone pole of the section 7L' of the solenoid. The contact-jaw q connectsby a wire with one pole of the section h of the solenoid. The oppositepoles of the sections h and 7L of the solenoid are connected by wires yy', respectively, with the contact-pins g g on the arm e4 at the back ofthe gage.

The operation of the switch may be brieiiy described as follows: Thegage having been set to maintain the pressure at twenty pounds, (2Olbs.,) as denoted by the pointer c', Fig. l, and the pressure havingfallen slightly below that amountsuflicient to bring the tonguefincontact with the pin g',the electric circuitV has been completed fromthe pin g to one pole of the section h of the solenoid, thence to theopposite pole of the solenoid, thence through wire te to the contact-jawq', thence through the core o to the jaw q, thence along branch wire uto main wire s, thence back along wire s and wire 'u to the vibratingtonguef and to the piu g', the point of starting. This will energize thesection h of the solenoid, causing the auxiliary core o to plungeagainst the shoulder o2 on the core o and force the latter out frombetween the jaws q q and into engagement between thejaws r' r. Thismovement of the core o will break the circuit through thesolenoid-section h by leaving a space between the jaws q q', and, whatis more im portant,will break the circuit between the vibrating tonguefand pin g,so that there will be no tendency for the contact at thatpoint to burn out when the movement of the tonguef slowly away from thepin g takes place, as will be hereinafter shown. This movement of thecore 0 will, however, close the circuit through the pump, as follows:Beginning with main wire s,through branch wire u to contact-jaw r,thence through coreo now in contact with the jaws r r to jaw r, thencethrough wire 'w and t to pump back to wire t, and wire o to the othermain-line wire s'. The action of the pump will continue until thepressure has reached the limit of twenty pounds, (2O lbs.,) to which thegage has been set, at which moment the tongue f will come intoengagement with the pins g, thereby completing circuit through thesection h of the solenoid, as follows: from pin g through wire g to onepole of the solenoid-section h', from the opposite pole of said sectionalong wire fw to the jaw r', thence through core o to jaw r, thencealong wire u to main-line wire s, thence back through main-line wire s'and along wire e to the vibrating tongue f and to the contact-pin z.This will energize the section 7L and move the core o, first moving theauxiliary core o', as before explained, away from the jaws r r and intoengagement with the jaws q q. By leaving the open space between the jawsr r the circuit through the section h of the solenoid and through thecontact-pin g/ and vibrating tongue f will be broken, so that there willbe no tendency to burn out its contact when the tongue f shall moveslowly away from the pin g, and at the same time the circuit through thepump will be broken as it is completed through the jaws r r', as abovedescribed. The pump will then stop until the pressure shall have fallenslightly below the predetermined amountin the present instance, twentypounds (2O lbs.)-j ust sufficiently below to bring the vibrating tonguef in contact with the pin g',

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when it will again be started, as above described. It will be observedthat the variation in the pressure will depend upon the distance thevibrating tongue fis permitted to move between the contact-pins g g',and this may be made so small that the variation in the pressure will bealmost imperceptible.

It is obvious that changes might be resorted to in the form,construction, and arrangement of the several parts without departingfrom the spirit and scope of my invention. Hence I do not wish to limitmyself strictly to the structure herein set forth; but

What I claim isl. In combination, a main-line circuit, a pump-circuit, apressure-gage, a solenoid and contact-pieces at the opposite ends of thesolenoid, the core of the solenoid being so located with respect to thesaid contact-pieces that it will make circuit through one set and breakcircuit through another set at each movement of the core, therebysimultaneously making or breaking circuit through the pump and breakingcircuit through the solenoid, substantially as set forth.

2. In combination, a main-line circuit, a

pump-circuit, a pressure-gage, a solenoid and means under the control ofthe gage for energizing the solenoid and thereby making and breaking thepump-circuit, the said means comprising a vibrating tongue xed to movewith the gage-arbor, an arm for swinging the gage-arbor together withthe vibrating ton gue into any position within the limits of the gageand contact-pieces carried by the said arm for limiting the vibratorymovement of the tongue in any position in which it may be set,substantially as set forth.

3. The combination with the reciprocating core of the solenoid, of anauxiliary core having a limited movement on the main core, substantiallyas set forth.

4. The combination with the solenoid, its core and yielding jaws forreceiving the opposite ends of the core, of an auxiliary core having alimited initial movement along the main core for imparting a drivingmovement to the main core to release it from the con tact-jaws,substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname, in presence of two witnesses, this Sth day of November, 1901.

ALFRED C. GRISCOM.

\Vitnesses:

FREDK. HAYNES, HENRY THIEME.

